This invention relates to a roller or cylinder construction and more particularly to a roller or cylinder which engages and cooperates with another roller or cylinder, the axes of which are substantially parallel, the engagement of the rollers with each other tending to flex one of the rollers.
There are many applications in the printing industry where deflections of only a few thousandths of an inch can cause serious deficiencies. Examples of such a pair of rollers or cylinders are the impression roller and plate cylinder of a gravure press, the ink rollers and plate cylinders of flexographic and letter presses, and the rollers for supplying ink and water to the plate cylinder of an offset press. Another example of the requirement for a uniform contact between two rollers is in calendering in the making of paper, for example.
U.S. Pat. No. 2,261,740 discloses cylinder structures in which a hollow cylinder is mounted for rotation about a sleeve surrounding a shaft. Relative motion between the sleeve and the shaft causes interacting camming elements to exert a radial force on the inside of the hollow cylinder intermediate the ends thereof to neutralize the prevailing deflecting stresses. These structures require considerable structure to be located inside the hollow cylinder midway of its length, which causes difficulties in the assembly of the cylinder as well as in the reliability and maintenance thereof.